Ebola virus disease (EVD) is a severe, often fatal illness in humans. The case fatality rate is around 50%. The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission. EVD first appeared in 1976 in 2 simultaneous outbreaks, one in Sudan, and the other in Democratic Republic of Congo. The latter occurred in a village near the Ebola River, from which the disease takes its name. The virus family Filoviridae includes 3 genera: Cuevavirus, Marburgvirus, and Ebolavirus. There are 5 species that have been identified: Zaire, Bundibugyo, Sudan, Reston and Taï Forest. The first 3, have been associated with large outbreaks in Africa. The virus causing the current outbreak belongs to the Zaire species.